The sedimentary record of the Larnaca salt lake, Cyprus: testing the impact of environmental changes on the Late Bronze Age abandonment of the harbor town Halla Sultan Tekke

An extensive complex of interconnected salt lakes, fringing the Mediterranean Sea between the town of Larnaca and Cape Kiti, marks the Larnaca coastal plain in Eastern Cyprus. The archaeological site of Hala Sultan Tekke (HST), identified as a Bronze age harbor town, is situated directly to the west of the main salt lake. Archaeological excavations (Aström et al. 1975-2007) revealed that the town was abandoned in the 11th century BC. The archaeological finds testify diverse (copper, wine, ware...) and long-distance trade relations with Crete, Syria, Palestine and Egypt during the Bronze Age.
Recent geological and coring investigations were carried out in the surroundings of the salt lake in order to study the palaeoenvironmental evolution of the coastline and to identify possible passageways for ships between the Mediterranean Sea and the inner harbour of HST during the Bronze Age. At the HST site, the main salt lake is protected from the Mediterranean Sea by a NE-SW trending Pleistocene sandstone barrier. A second Middle to Late Holocene ridge, separates the whole complex of interconnected salt lakes from the present-day Mediterranean sea.
Hand-operated augering took place in the main salt lake, close to the HST site, as well as in the southernmost lake (Menoui beach) close to the present-day coastline. The facies of the sediment succession in the cores are identified on the basis of lithology, sedimentary structures and macrofossils. Data from mechanical drilling logs (Geological Surface of Cyprus) are integrated to establish the bedrock topography.

The preliminary field results indicate that the sedimentary sequence can be subdivided into Pliocene bedrock (Marl), open marine, lagoon, coastal marsh, salt lake and coastal ridge deposits. The open marine sedimentary unit is made up of horizontal packs of fibres and rhizomes of the marine phanerogam Posidonia Oceanica, alternating with beds of bluish-grey sandy , rich in open-marine shells (Abra tenuis, Venerupis aureus). These Posidonia fibers are not in situ but originate from sub littoral meadows nearby. The latter suggest that the bay of Larnaca was open, but protected; its floor being built up behind a Posidonia meadow, which absorbed swells and trapped fine particles. This open marine Posidonia sedimentary unit is mainly found in the sedimentary succession of boreholes located in the southern lake (near Menoui beach), where it is covered by rather thin layers (up to 0.5 m) of lagoon and salt-lake deposits.
Close to the HST site, the sedimentary succession in boreholes reflects a more confined marine embayment because of the presence of a Pleistocene barrier. This more confined marine embayment gradually evolved into lagoon, coastal marsh and finally to an enclosed salt lake as a result of the development of a Middle to Late Holocene coastal ridge along the present-day shoreline. This coastal ridge consists of up-to 10 m thick -packages of accumulated pebbles, overlying Posidonia- rich open marine deposits.

Based on the preliminary results, it is suggested that during the early Holocene, an open, but protected, marine embayment developed behind a Posidonia meadow. A coastal spit developed rapidly towards the northeast (pebbles transported by long shore drift from an erosion front at Cape Kiti and from the Tremithos river mouth), progressively isolating a lagoon that became enclosed, silted up and eventually evolved into the present-day salt lake. Historical sources document that from the 16th century onwards, the lake became one of the most important locations for salt extraction in the Mediterranean.